Ocean beta - Make music with friends in your browser
Meludia - Listening exercises and to sharpen your ear and music theory skills
iO-808 - Rhythm composer modeled after Roland's TR-808 drum machine.
GNU Solfege - GNU Solfege is free music education software.
Cameo - Book personalized video shoutouts from your favorite people
Perfect Ear - A simple yet advanced application for improving your solfege skills.